Women Health Expert: Birth Control Changes Who You Are & How You Feel About Your Partner!

Here are the top 10 key takeaways from Dr. Sarah Hill's conversation about how birth control changes women's bodies, minds, and relationships—insights every woman and the people who love them should know.

1. Hormonal birth control changes who women are

The birth control pill fundamentally changes women by altering their hormones, which are crucial to how the brain creates the experience of being who we are. Dr. Hill discovered this after being on hormonal birth control for over a decade. When she discontinued it, she felt like she "woke up" - experiencing deeper emotions, renewed interest in sex, more energy, and greater engagement with life.

These changes happen because the pill suppresses ovulation by giving women a combination of synthetic hormones that tell the brain not to stimulate the ovaries. This flatlines a woman's natural hormone production and replaces it with a daily dose of synthetic progesterone (progestin) and sometimes a low level of estrogen. Many women don't realize these significant changes are happening to them while on the pill.

2. The pill affects who women are attracted to

Research shows that women on hormonal birth control have different partner preferences compared to naturally cycling women. During natural cycles, women experience an estrogen surge around days 9-15, which increases their preference for masculine traits and testosterone markers in potential partners. The pill eliminates this surge and keeps estrogen levels consistently low.

Women on the pill tend to prefer less masculinized male faces, voices, and behaviors than naturally cycling women. This can create relationship issues when women meet partners while on the pill and later discontinue it. Studies show that women partnered with attractive men became more attracted to their partners after going off the pill. Conversely, women partnered with less attractive men became less attracted to their partners after discontinuing hormonal contraception.

3. Hormonal contraception can reduce women's libido

The birth control pill often decreases women's sexual desire through multiple mechanisms. Normally, rising estrogen levels during a woman's cycle fuel the female sexual response, especially around ovulation when pregnancy is possible. The pill eliminates these natural peaks in desire by flatlining hormone levels.

Additionally, synthetic hormones in birth control increase sex hormone binding globulin, which binds free testosterone and makes it inactive in the body. Women on hormonal birth control have approximately 60% lower free testosterone levels than naturally cycling women. Since testosterone is important for sexual desire in both men and women, this significant reduction further suppresses women's libido, creating what Dr. Hill describes as "another blow to women's sexual desire."

4. The pill impacts emotional states and stress responses

Research shows that women on hormonal birth control have a blunted cortisol response to stress. While chronic high cortisol is harmful, dynamic spikes in cortisol during stressful events are actually adaptive and help us regulate and cope with stress. Women on the pill don't experience these normal cortisol responses.

This blunted stress response resembles what's seen in people with PTSD or trauma, whose bodies suppress cortisol release after experiencing chronic stress. This hormonal disruption can lead to disregulated immune and emotional responses. Danish studies found women on the pill were 50% more likely to be diagnosed with depression within six months of starting it, and twice as likely to have attempted suicide compared to naturally cycling women.

5. Women's mating preferences are evolutionarily shaped

Throughout evolutionary history, women were dependent on men for resources while pregnant and caring for children. This created selection pressure favoring women who preferred partners with status and resources. Modern women have inherited this psychology, which explains why even financially independent women still prefer partners with comparable or greater resources and status.

This evolutionary legacy creates what some researchers call a "mating crisis." As women become increasingly educated and financially successful, they continue to prefer partners with at least equal status and resources. With women now comprising about 60% of college students and outpacing men educationally, many successful women struggle to find suitable partners who meet their evolved preferences. Rather than "dating down," many women choose to remain single.

6. Men and women have different risk preferences

Men are generally more risk-tolerant than women, a difference shaped by evolutionary history. Women's bodies and evolutionary roles led to more risk-averse psychology since they spent much of their reproductive lives pregnant and caring for young children. Being cautious promoted survival of offspring.

Men's psychology evolved to be more risk-seeking because the potential reproductive benefits of winning big were much greater for men than women. This principle, called the Bateman principle, notes that men's reproductive success can increase with each new partner, while women's tops out after one partner per reproductive cycle. This difference explains why more men engage in high-risk behaviors like gambling and entrepreneurship, though risk-taking doesn't necessarily translate to better performance in business.

7. Birth control affects physical performance

Recent research shows that women on hormonal birth control have more difficulty building muscle mass compared to naturally cycling women. In one study, women doing identical exercise routines over 12 weeks showed significant differences in results. Those on birth control gained less muscle and had lower testosterone levels than naturally cycling women.

This happens because birth control suppresses testosterone production, which stimulates muscle growth. Additionally, AMPK levels, which also promote muscle development, tend to be higher when estrogen is high during natural cycles. With birth control flatlining these hormones, women's fitness and athletic performance can be negatively affected, something many women aren't told when prescribed hormonal contraception.

8. Teenage girls face specific risks from hormonal birth control

Dr. Hill expressed particular concern about teenage girls using hormonal birth control during critical periods of brain development. The teenage brain is still developing, and the pubertal transition involves remodeling from the child version to the adult version, a process coordinated by sex hormones.

Replacing natural hormonal patterns with synthetic hormones during this critical developmental window could have long-lasting consequences. Limited research suggests it may increase long-term risk of major depressive disorder, even after discontinuing the pill. With teenage girls already facing higher risks of mental health issues while on hormonal birth control, Dr. Hill recommends non-hormonal alternatives like the copper IUD when possible.

9. Father-daughter relationships influence female development

Research shows that girls whose fathers are absent or uninvested during childhood tend to have different developmental trajectories. These girls typically enter puberty significantly earlier than girls from two-parent homes with investing fathers. They also tend to begin sexual activity earlier and have more sexual partners over time.

This pattern demonstrates how family dynamics can influence biological development and sexual behavior. While the research hasn't linked this to earlier menopause, studies have found that father absence or lack of investment can affect girls' ovarian reserve and shape their reproductive strategies. This connection between family structure and sexual development highlights how social environments can influence biological processes.

10. Better birth control options are needed

Despite being one of the most important developments for women's independence, hormonal birth control comes with significant tradeoffs that aren't adequately addressed in medical settings. Dr. Hill argues that we need more and better options beyond just changing women's hormones. Current alternatives like the copper IUD work for some women but aren't suitable for everyone.

The medical community has often considered birth control a "solved problem," but this view overlooks the substantial side effects many women experience. Dr. Hill advocates for more research into alternative contraceptive methods that don't disrupt women's hormonal systems. Her work aims to empower women with information so they can make informed decisions about their bodies while highlighting the need for innovation in reproductive health options.