Female athletes train and compete under the potential influence of hormonal fluctuations during the menstrual cycle (MC) or during use of various hormonal contraceptives (HCs). Other female athletes may have menstrual disturbances and amenorrhea, which are more common among athletes compared to the general population (Redman and Loucks, 2005; Torstveit and Sundgot-Borgen, 2005; Nattiv et al., 2007). Although such hormonal impact may exert a significant influence on training and physical performance, recent studies request more knowledge in the field (Costello, Bieuzen and Bleakley, 2014; Bruinvels et al., 2017; Janse DE Jonge, Thompson and Han, 2019; Findlay et al., 2020; Cowley et al., 2021). Specifically, there is a lack of sufficiently large studies reporting results on sub-groups at different levels of performance both without and with different types of HCs.

The MC can be divided into three specific phases: the follicular phase (menses to ovulation), the ovulatory phase (at mid-cycle and lasts 24–48 h), and the luteal phase (from ovulation to next menses) (Hirschberg, 2022). Although the levels of estradiol and progesterone vary significantly during these phases, previous research investigating the effect of the MC on physical performance has shown varying results (Giacomoni et al., 2000; Oosthuyse, Bosch and Jackson, 2005; Bushman, Masterson and Nelsen, 2006; Shaharudin, Ghosh and Ismail, 2011; Vaiksaar et al., 2011; Julian et al., 2017; Barba-Moreno et al., 2019; McNulty et al., 2020; Taipale-Mikkonen et al., 2021). A recent meta-analysis concluded that muscle strength, as well as maximal and submaximal aerobic performance, are trivially reduced during the early follicular phase (during menses, low levels of estradiol, and progesterone), compared with all other MC phases (McNulty et al., 2020). However, the meta-analysis emphasized that general guidelines on the effects of the MC on exercise performance can yet not be formulated due to methodological limitations of the included studies (McNulty et al., 2020). Most studies were underpowered, lacking clear definition of cycle phase and have not considered dysmenorrhea, variation in general well-being or premenstrual symptoms (PMS) during the cycle. There is a lack of studies investigating menstrual related symptoms on self-reported effects of muscle strength, aerobic fitness, mental sharpness, balance, and sleep quality in a large group of athletes in different sports and performance levels.

The use of HCs in the general population of Scandinavian women of reproductive age is approximately 40% (Lindh et al., 2017). A higher proportion, 50%–57%, of HC use has been reported for different athlete populations in various European countries (Martin et al., 2018; Oxfeldt et al., 2020; Solli et al., 2020; Nolan, Elliott-Sale and Egan, 2022), and Engseth et al. (Engseth et al., 2022) showed a proportion of 68% in Norwegian cross-country skiers and biathletes. In general, combined oral contraceptives (OCs) containing estrogen and progestin are reported as more commonly used (60%–74% of athletes) in athletes compared to progestin-only HCs (Martin et al., 2018; Oxfeldt et al., 2020; Solli et al., 2020). However, the Norwegian study showed inverse proportions with 36% using combined OCs and 64% progestin-only (Engseth et al., 2022). A recent meta-analysis by Elliott-Sale and colleagues (2020) concluded that combined OCs may slightly reduce exercise performance compared to non-HC use (Elliott-Sale et al., 2020). Hypothetically, this might at least partly be related to side effects of HCs including mood changes (Zethraeus et al., 2016; Lundin et al., 2017; Ekenros et al., 2019). The influence of various HCs on physical performance in athletes at different competition levels has earlier been studied in cross-country skiers and biathletes (Engseth et al., 2022), but data from other sports are currently lacking.

Accordingly, more detailed knowledge concerning the perceived impact of the MC and different administration of HCs on the training and performance of female participants in different sports and performance levels is required. Therefore, the current investigation was designed to 1) characterize perceptions of training and performance during the MC phases and by HC use in a large population of female athletes; 2) explore whether symptoms experienced during different phases of the MC and HC use are related to perceived performance; and 3) examine potential differences in these respects between athletes within different levels of performance.

Of 1,109 respondents, 1,086 athletes from 57 different sports (Table 1) consented to participate in the study. Those 1,086 athletes were divided into non-users (37%, n = 407) and HC users (63%, n = 679) (Figure 1) and their demographic characteristics are documented in Table 2.

Most of the athletes experienced menarche within normal age range (93%), Table 2. Dysmenorrhea was reported by 68% (n = 742) of all the athletes. Of those, 72% (n = 534) reported to use medication for pain relief. The use of pain relief without prescription was most frequently reported, by 65% (n = 485) of the athletes, pain relief with prescription was used by 7% (n = 50), and 13% (n = 99) of the athletes reported use of OCs as treatment for dysmenorrhea. The non-HC users experienced dysmenorrhea significantly more frequent than the HC users (p = 0.003, w = 0.09). On the other hand, a history of secondary amenorrhea was reported more frequently by HC users than non-users (43% vs. 35%). Of those with previous amenorrhea, 32% (n = 139) and 29% (n = 128) related their amenorrhea to increased amount of training or weight loss, respectively.

Out of all the athletes, 76% (n = 824) believed that their MC or use of HCs could have some or a high impact on their performance at training, and 73% (n = 791) on their competitive performance (partial or high impact). Despite this, only 18% (n = 191) of the athletes reported to partially or to a high extent scheduling their training based on their MC or use of HCs. Altogether, 45% (n = 494) of the athletes had refrained from planned training, and 14% (n = 151) from competition for reasons related to their MC or use of HCs (Table 3). The most common reason to refrain from training or competition was menstrual related pain (33%, n = 353 and 11%, n = 118, respectively). Generally, there was no significant difference between the non-HC users and HC users in refraining from training (48%, n = 196 and 44%, n = 298) p = 0.171, w = 0.04 or from competition (15%, n = 60 and 13%, n = 91), p = 0.532, w = 0.02 (Table 3). However, the non-HC users refrained significantly more frequent from training due to mental symptoms of PMS (e.g., depression, irritability, loss of concentration, tearfulness), compared to the HC users (7%, n = 27 and 4%, n = 26), p = 0.003, w = 0.06).

This is by far the largest study reporting symptoms related to the MC and HC use in athletes and their perceived impact on physical performance at different levels of performance. We found that symptoms related to the MC are common across all athlete levels, particularly dysmenorrhea and PMS which also seem to influence perceived performance of aerobic fitness, muscle strength, mental sharpness, balance, and sleep quality. A large proportion of the athletes (63%) used HC and perceived a variety of side-effects. However, performance was experienced equally independent of time-point of the pill-chart except for the period of inactive pills, which was associated with the most negative impact. Nonetheless, few of the athletes consider MC or HC issues when planning their training or competitions.

A MC length within normal range was reported by most of the non-HC users. However, ten percent of the athletes reported a current secondary amenorrhea and six percent reported their MC to be > 35 days, indicating oligomenorrhea. This agrees with previous research reporting that menstrual irregularities, such as amenorrhea and oligomenorrhea, is common among elite athletes, potentially due to relative energy deficiency (RED-S) and extensive training (Torstveit and Sundgot-Borgen, 2005; Nattiv et al., 2007; Joy et al., 2014).

The non-HC users in our study perceived a negative impact on several aspects of performance during the early follicular phase (menstrual bleeding) and during the late luteal phase, compared to the ovulation phase of the MC. The negative impact on performance was in turn showed to be related to menstrual pain during the early follicular phase and PMS during late luteal phase. This agrees with Martin et al. (2018) and Solli et al. (2020) who discussed a likely relationship between symptoms such as dysmenorrhea and/or PMS and an impact of performance during these phases.

Even though most of our athletes (74%) were affected by menstrual related pain, only one third reported that this pain led them to refrain from training. In comparison, Solli et al. (2020) found that 22% of their female athletes altered their training repeatedly due to negative effects of the MC, while Martin et al. (2018) reported a corresponding frequency of only 4%. A related qualitative study concluded that although female athletes’ express acceptance of menstrual related symptoms, they do not consider such symptoms to be sufficient reason to refrain from training and are reluctant to discuss their symptoms with their coaches (Findlay et al., 2020).

There are effective medical treatments for pain relief of dysmenorrhea. The first choice of treatment regimen is non-steroid anti-inflammatory drugs (NSAID) and/or hormonal suppression by combined OC treatment (Wong et al., 2009). To reduce the severity of symptoms, 52% of the athletes in the study by Solli et al. (2020) reported to have used painkillers. Data from our study show that 72% of the athletes with dysmenorrhea used medical treatment for pain relief and most common were different painkillers without and with prescription, 65% and 7% respectively. OCs as treatment for dysmenorrhea was used by 13% of the athletes. These results suggest that many athletes in our study did not use adequate treatment. However, there is a need for more knowledge of how different types of treatment regimens for dysmenorrhea affects the results of training and performance.

PMS is characterized by several MC-related symptoms, both somatic (breast tenderness, bloating, headache) and mood/mental symptoms (irritability, depression, tearfulness, fatigue) during the luteal phase of the MC (Angst et al., 2001). Among the 78% of our respondents who experienced PMS, irritability was the most frequent reported symptom. Overall, these female athletes perceived a negative impact on overall physical performance, aerobic fitness, muscle strength, mental sharpness, postural control, and quality of sleep in the late luteal phase of the MC.

A recent meta-analysis of studies involving objective determination of muscular and aerobic performance during different phases of MC, concluded that performance was only trivially decreased during the early follicular phase compared to the ovulatory and luteal phase (McNulty et al., 2020). Additionally, an altered postural control in the luteal phase has been observed (Darlington et al., 2001), especially in women experiencing PMS (Fridén et al., 2003; Fridén et al., 2005). It might be that the influence of the MC on physical performance is not primarily mediated via the hormonal changes during the different phases, but indirectly through MC-related symptoms like dysmenorrhea, PMS and reduced quality of sleep since these symptoms was related to performance among the athletes in our study.

The majority of the athletes (63%) in this study were using HCs, which is a higher proportion than among the general population (Lindh et al., 2017), as well as among other groups of elite athletes (Martin et al., 2018; Oxfeldt et al., 2020; Solli et al., 2020; Nolan, Elliott-Sale and Egan, 2022). However, Engseth et al. (2022) showed a similar proportion, 68%, in cross-country skiers and biathletes. Progestin-only HCs and combined HCs were equally common, with a slight predominance for progestins (52% vs. 48%, respectively). This contrasts with Martin et al. (2018) and Solli et al. (2020) reporting a higher proportion of combined HCs. The relatively high use of progestins in our study could be explained by the promotion of long-acting reversible contraception (LARC), including hormonal IUD and implants, in recent years in the Nordic countries to provide effective contraception for an extended period of time (Lindh et al., 2017) which also was reported by Furu et al. (2021) and Engseth et al. (2022). In agreement with earlier reports (Martin et al., 2018; Solli et al., 2020), oral administration of combined OCs was the most common combined method in our athletes compared to vaginal ring or patch.

In addition to birth control, OCs are utilized to treat dysmenorrhea, menorrhagia, amenorrhea, as well as to postpone or omit menstrual bleeding (Elliott-Sale et al., 2020), which was also the case among the athletes in our study. As expected, dysmenorrhea was significantly less frequently reported by HC users than non-HC users in our study. Back-to-back OC cycles (i.e., skipping the days of inactive pills) designed to avoid bleeding, were reported by 47% of our athletes. This is not surprising considering earlier observations on the application of this strategy to manipulate and alleviate symptoms related to menstrual bleeding (Martin et al., 2018; Schaumberg et al., 2018). Perceived side-effects of HC use were common and reported by 40% of the users. However, we found no significant difference in the prevalence or nature of side effects between those taking progestins only or combined HCs.

Almost half of the athletes using combined OCs reported perceived influence of OCs on physical performance. However, the general picture was a negative impact during the inactive phase of the pill chart when usually a withdrawal bleeding occurs and not in association with intake of hormone-containing pills. Dysmenorrhea seems to be the most important factor related to negative impact on physical performance by OC users. Although quite many of the athletes already today skip the inactive pills, it could be further recommended to achieve absence of menses and no pain.

The proportion of HC users among those at top-elite level was lower (55%) compared to those at sub-elite level (67%). In this context, the lack of conclusive evidence concerning the impact of HCs on physical and mental performance (Elliott-Sale et al., 2020) might have influenced the willingness of our elite athletes to use HCs. Weight gain is one such potential side effect and 20% of our respondents experienced weight gain, in comparison to approximately 8% reported by Martin et al. (Martin et al., 2018). However, there is no evidence of a causal relationship between combined OCs and weight gain (Gallo et al., 2014).

This big dataset shows that menstrual related symptoms are common in female athletes across all athlete levels and often impact their training and performance. However, few athletes schedule their training or competition in relation to these symptoms. Dysmenorrhea and PMS are the most common symptoms and are perceived to negatively relate to different aspects of performance such as aerobic fitness, muscle strength, mental sharpness, balance, and sleep quality. A large proportion of the athletes used HCs, with progestins as the most common method, not only for contraception but also to treat various menstrual related symptoms. Even though side-effects were reported, physical performance such as aerobic fitness, muscle strength, mental sharpness, balance, and sleep quality did not seem to vary during the pill-chart of combined OCs with exception from the time point of inactive pills, which was associated with a negative impact. The results of this survey of 1,086 female athletes indicate that greater focus should be on identifying and effectively treat different MC or HC related symptoms on an individual level.