ABSTRACT
Introduction:
Contraceptive methods are widely used, yet their impact on menstrual cycle regularity remains a topic of clinical significance. This study aims to investigate how different contraceptive methods influence menstrual cycle regularity in reproductive-age women.
Methods:
A randomized controlled trial was conducted on 300 women, aged 18-45, categorized into three groups: oral contraceptives, intrauterine devices (IUDs), and hormonal implants. Menstrual cycle regularity, defined by the number of cycles within 28-32 days, was assessed over six months.
Results:
Oral contraceptives resulted in the most regular cycles (P < 0.05), followed by IUDs. Hormonal implants had a higher incidence of irregular cycles.
Conclusion:
Oral contraceptives promote the highest regularity in menstrual cycles, followed by IUDs. Hormonal implants showed higher variability in cycle regularity.
KEYWORDS: Contraceptives, menstrual cycle, randomized controlled trial, regularity, women’s health
INTRODUCTION
The impact of contraceptive methods on menstrual cycle regularity has been the focus of research in recent years. Various forms of contraception, such as oral contraceptives, intrauterine devices (IUDs), and hormonal implants, have shown differential effects on the menstrual cycle. Regular menstrual cycles, typically occurring every 28 to 32 days, are indicative of hormonal balance, while irregular cycles can be associated with underlying health conditions. This study aims to compare the effects of different contraceptive methods on menstrual cycle regularity in reproductive-age women.
Studies have shown that hormonal contraceptives, particularly oral contraceptives, regulate menstrual cycles by maintaining consistent hormone levels.[1,2] However, the impact of other methods such as IUDs and hormonal implants on cycle regularity has not been thoroughly compared in a randomized controlled trial setting.[3,4,5] Understanding these effects will provide critical insights into choosing the appropriate contraceptive method.
METHODS
A randomized controlled trial was conducted among 300 women, aged 18-45, who were allocated into three groups: oral contraceptives (n = 100), intrauterine devices (n = 100), and hormonal implants (n = 100). Participants were followed for six months. Menstrual cycle regularity was assessed monthly, with regularity defined as cycles between 28 and 32 days. Exclusion criteria included previous diagnosis of endocrine disorders or irregular menstrual cycles. Parameters assessed included age, BMI, duration of contraceptive use, and smoking status. Data were analyzed using ANOVA and post-hoc tests for statistical comparisons, with significance set at P < 0.05.
RESULTS
Table 1 highlights significant differences in menstrual cycle regularity among users of different contraceptive methods. Oral contraceptive users exhibited the highest regularity, with 85% of participants reporting cycles within the 28-32 day range. In contrast, 70% of women using intrauterine devices (IUDs) experienced regular cycles, while hormonal implant users reported the lowest rate of regularity at 55%. These findings indicate that oral contraceptives are the most effective method for achieving consistent menstrual cycles (P < 0.05). Both IUDs and hormonal implants resulted in higher rates of irregular cycles compared to oral contraceptives, with the latter showing the greatest variability in menstrual patterns.
Table 1.
Menstrual cycle regularity across different contraceptive methods
| Group | Regular Cycles (%) | Irregular Cycles (%) | P |
|---|---|---|---|
| Oral Contraceptives | 85% | 15% | <0.05 |
| IUDs | 70% | 30% | <0.05 |
| Hormonal Implants | 55% | 45% | <0.05 |
Table 2 explores the impact of BMI on menstrual cycle regularity across the different contraceptive methods. Among women with normal BMI, those using oral contraceptives had the highest regularity, with 88% reporting consistent cycles. IUD users in this category also experienced relatively high regularity (72%), while hormonal implant users had a lower rate of 58%. In the overweight/obese category, regularity decreased across all groups, with 82% of oral contraceptive users, 68% of IUD users, and 50% of hormonal implant users reporting regular cycles. These results suggest that BMI influences menstrual regularity, particularly for hormonal implant users, where overweight/obese women showed a pronounced decline in regularity. Statistical analysis confirmed that these differences were significant (P < 0.05).
Table 2.
Comparison of menstrual cycle regularity by BMI
| BMI Category | Oral Contraceptives (%) | IUDs (%) | Hormonal Implants (%) | P |
|---|---|---|---|---|
| Normal Weight | 88% | 72% | 58% | <0.05 |
| Overweight/Obese | 82% | 68% | 50% | <0.05 |
DISCUSSION
The results of this study suggest that oral contraceptives are more effective in maintaining menstrual cycle regularity compared to IUDs and hormonal implants. These findings are consistent with previous studies showing that oral contraceptives stabilize hormone levels, which directly influence menstrual regularity.[6,7]
Interestingly, IUDs showed moderate effectiveness in regulating the cycle, likely due to their local effect on the endometrium without systemic hormonal influence.[8] Hormonal implants, on the other hand, were associated with higher rates of irregular cycles, which may be due to the progestin-only nature of the implant, causing erratic hormone fluctuations.[9,10]
This study also observed a relationship between BMI and menstrual cycle regularity across all methods, with overweight and obese women experiencing more irregular cycles. This highlights the importance of considering individual patient factors when prescribing contraceptives. Further research is needed to explore long-term effects and patient satisfaction.
CONCLUSION
This randomized controlled trial demonstrates that oral contraceptives are the most effective method for maintaining menstrual cycle regularity compared to intrauterine devices (IUDs) and hormonal implants. The study highlights that oral contraceptive users experienced the highest rate of regular cycles, followed by IUD users, while hormonal implant users had a significantly higher rate of irregular cycles. Additionally, factors such as BMI were found to influence menstrual regularity, particularly among women using hormonal implants, where those with higher BMI exhibited more irregular cycles. These findings underscore the importance of considering both contraceptive methods and individual factors like BMI when recommending contraceptive options. Further research is needed to evaluate long-term outcomes and patient satisfaction with various contraceptive methods to better inform clinical decisions and provide personalized care to women.
Conflicts of interest
There are no conflicts of interest.
Funding Statement
Nil.
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