What Pill Is Used to Regularize Your Period? A Guide to Medications

October 12, 2025 •

4 min read

An estimated 14% to 25% of women of childbearing age experience menstrual irregularities [1.9.1]. If you're wondering what pill is used to regularize your period, several medical options are available, primarily focusing on hormonal regulation to create a predictable cycle.

Quick Summary

Various pills can help manage and regularize menstrual cycles. The most common are combination hormonal contraceptives, progestin-only therapies, and medications like metformin that address underlying issues like PCOS.

Key Points

Hormonal Contraceptives are a First-Line Treatment: Combination pills containing estrogen and progestin are commonly used to create regular, predictable withdrawal bleeds [1.4.1].
Progestin-Only Options Exist: For those who can't take estrogen, cyclic progestin therapy (like medroxyprogesterone) can induce periods, while progestin-only pills offer a continuous option [1.2.1, 1.5.5].
Underlying Causes Must Be Addressed: Conditions like PCOS and thyroid disorders are common causes of irregular periods and may require specific treatments like Metformin or thyroid medication [1.6.1, 1.10.3].
Metformin for PCOS: Metformin helps regulate periods in many women with PCOS by improving insulin sensitivity and restoring ovulation [1.6.2].
Diagnosis is Crucial: A healthcare provider must determine the cause of irregularity before the correct pill can be prescribed [1.10.3].
Non-Contraceptive Benefits: Many pills used for regulation also offer benefits like reduced cramps, lighter periods, and clearer skin [1.11.1].
Lifestyle Plays a Role: Maintaining a healthy weight, managing stress, and moderate exercise can help regulate periods naturally [1.8.3].

Understanding and Treating Irregular Periods

An irregular menstrual cycle, where the length of your cycle is unpredictable, can be a source of anxiety and concern. A normal cycle typically ranges from 21 to 35 days [1.9.2]. Irregularity can manifest as infrequent periods (oligomenorrhea), absent periods (amenorrhea), or unpredictable timing [1.10.2]. Before seeking treatment, it's crucial to understand the underlying cause, which can range from lifestyle factors to medical conditions.

Common Causes of Irregular Menstruation

A healthcare provider will first investigate why your periods are irregular. Common causes include:

Polycystic Ovary Syndrome (PCOS): A hormonal disorder that is one of the most common causes of irregular periods [1.10.2].
Thyroid Disorders: Both an underactive (hypothyroidism) and overactive (hyperthyroidism) thyroid can affect your hormones and cause menstrual irregularities [1.10.3].
Stress: High levels of physical or emotional stress can disrupt the hormonal balance that governs your menstrual cycle [1.10.3].
Significant Weight Changes or Low Body Fat: Gaining or losing a lot of weight, or having very low body fat from intense exercise, can impact menstruation [1.8.3].
Uterine Issues: Conditions like uterine fibroids or polyps can lead to abnormal bleeding [1.10.3].
Perimenopause: The transitional period before menopause when hormone levels begin to fluctuate [1.10.3].

Hormonal Medications for Period Regulation

Hormone-based pills are the most common and effective treatments for creating a regular, predictable menstrual cycle. They work by controlling hormone levels, which in turn controls the buildup and shedding of the uterine lining.

Combination Hormonal Contraceptives

These are often the first-line treatment for regulating periods [1.4.1]. They contain both synthetic estrogen and progestin and are available in several forms:

The Pill: Oral contraceptive pills typically come in packs with 21-24 active hormone pills and 4-7 inactive (placebo) pills. The withdrawal of hormones during the placebo week triggers a predictable bleed, simulating a regular period [1.4.2].
The Patch: A patch worn on the skin that releases estrogen and progestin. It's changed weekly for three weeks, followed by a patch-free week to allow for a period [1.4.5].
The Vaginal Ring: A flexible ring inserted into the vagina that releases hormones. It's left in for three weeks and removed for one week to induce a period [1.4.1].

These methods work by suppressing ovulation and creating a thin, stable uterine lining, which leads to lighter, more regular, and less painful withdrawal bleeds [1.4.1].

Progestin-Only Therapy

For individuals who cannot or prefer not to take estrogen, progestin-only medications are an excellent alternative. Progestin is a synthetic form of the hormone progesterone [1.5.4].

Cyclic Progestin Therapy: Medications like medroxyprogesterone (Provera) or norethindrone (Aygestin) are often prescribed [1.2.1, 1.2.5]. A typical regimen involves taking the pill for 5 to 10 days each month to trigger a menstrual bleed a few days after stopping the medication [1.2.2]. This method is used to treat amenorrhea (absence of periods) and irregular bleeding but does not provide contraception [1.2.1].
Progestin-Only Pills (Mini-Pills): These pills contain a low dose of progestin and are taken every single day without a break. While they can make periods lighter or even stop them altogether, they are more commonly associated with unpredictable spotting, especially initially [1.5.5].

Non-Hormonal and Targeted Medications

Sometimes, the best pill to regulate your period isn't a hormone at all but one that targets an underlying medical condition.

Metformin

Metformin is a medication primarily used to treat type 2 diabetes, but it is frequently prescribed off-label for individuals with Polycystic Ovary Syndrome (PCOS) [1.6.1, 1.6.2]. Many people with PCOS have insulin resistance, which can lead to higher androgen (male hormone) levels and disrupt ovulation. Metformin improves the body's sensitivity to insulin, which can help lower androgen levels, restore regular ovulation, and thus regulate the menstrual cycle [1.6.2, 1.6.4]. It may take several months to see an effect, and it is often used in conjunction with lifestyle changes [1.6.2].

Medications for Other Underlying Conditions

Thyroid Medication: If hypothyroidism is the cause of irregular cycles, a medication like levothyroxine will be prescribed to restore normal thyroid hormone levels, which often corrects the menstrual problem.
Tranexamic Acid: This is a non-hormonal medication that can be used to treat very heavy menstrual bleeding (menorrhagia) but does not regulate the cycle's timing [1.7.2].

Comparison of Common Pills


Medication Type	How It Works	Primary Use Case	Side Effects	Contraceptive?
Combination Pills	Suppresses ovulation; stabilizes uterine lining with estrogen and progestin [1.4.1].	Period regulation, contraception, treating PCOS symptoms [1.4.4].	Nausea, headaches, breast tenderness, spotting, risk of blood clots [1.11.1].	Yes
Cyclic Progestin	Induces a withdrawal bleed by mimicking the natural fall of progesterone [1.2.1].	Inducing periods in amenorrhea; regulating cycles without contraception [1.2.1].	Mood changes, bloating, spotting, weight changes [1.2.1].	No
Metformin	Improves insulin sensitivity, which helps restore ovulation in people with PCOS [1.6.2].	Women with irregular periods due to PCOS and insulin resistance [1.6.1].	Nausea, diarrhea, abdominal bloating (often temporary) [1.6.3].	No

Conclusion: Consulting Your Doctor Is Key

While several types of pills can effectively regulate your period, the right choice depends entirely on your individual health profile, the underlying cause of the irregularity, and your personal preferences (such as whether you also need contraception). Combination hormonal contraceptives are a common starting point, while progestin-only therapy and targeted medications like metformin offer effective alternatives for specific conditions like estrogen sensitivity or PCOS [1.4.1, 1.5.4, 1.6.1].

It is essential to consult with a healthcare provider. They can perform the necessary tests to diagnose the cause of your irregular cycles and recommend the safest and most effective medication for your needs. Self-treating with medication without a proper diagnosis can mask serious health issues and lead to unwanted side effects.

Authoritative Link: For more information on menstrual irregularities, you can visit the Mayo Clinic.

Frequently Asked Questions

It can take a few months for your body to adjust to hormonal birth control. You might experience spotting or irregular bleeding initially, but your cycle should become regular after 2-3 months of consistent use [1.11.4].

Yes, depending on the cause. If the irregularity is due to PCOS with insulin resistance, a non-hormonal medication like metformin may help [1.6.2]. Lifestyle changes such as stress management, maintaining a healthy weight, and moderate exercise can also help regulate your cycle [1.8.3].

Medroxyprogesterone is a progestin-only medication typically taken for a short duration (e.g., 5-10 days) each month to induce a period; it is not a contraceptive [1.2.1, 1.2.2]. Birth control pills usually contain both estrogen and progestin and are taken continuously (with a placebo week) to prevent pregnancy and regulate cycles [1.4.1].

Yes, it's likely. The pill regulates your period by controlling your hormones. Once you stop taking it, your body will return to its natural cycle. If your periods were irregular before, they will likely become irregular again [1.11.4].

Common side effects, especially in the first few months, can include nausea, headaches, breast tenderness, and spotting between periods. These often improve over time. More serious risks, though rare, can include blood clots with estrogen-containing pills [1.11.1].

You should see a healthcare provider if your cycles are consistently shorter than 21 days or longer than 35 days, if you miss more than three periods in a row, if your bleeding becomes extremely heavy, or if you have severe pain [1.9.2, 1.10.3].

Yes, significant physical or psychological stress can disrupt the balance of hormones that control your menstrual cycle, leading to delayed or missed periods [1.10.4].