Melanie Guldi

Fertility Effects of Abortion and Birth Control Pill Access for Minors

This article empirically assesses whether age-restricted access to abortion and the birth control pill influence minors’ fertility in the United States. There is not a strong consensus in previous literature regarding the relationship between laws restricting minors’ access to abortion and minors’ birthrates. This is the first study to recognize that state laws in place prior to the 1973 Roe v. Wade decision enabled minors to legally consent to surgical treatment—including abortion—in some states but not in others, and to construct abortion access variables reflecting this. In this article, age-specific policy variables measure either a minor’s legal ability to obtain an abortion or to obtain the birth control pill without parental involvement. I find fairly strong evidence that young women’s birthrates dropped as a result of abortion access as well as evidence that birth control pill access led to a drop in birthrates among whites.

Maybe Next Month? Temperature Shocks, Climate Change, and Dynamic Adjustments in Birth Rates

Dynamic adjustments could be a useful strategy for mitigating the costs of acute environmental shocks when timing is not a strictly binding constraint. To investigate whether such adjustments could apply to fertility, we estimate the effects of temperature shocks on birth rates in the United States between 1931 and 2010. Our innovative approach allows for presumably random variation in the distribution of daily temperatures to affect birth rates up to 24 months into the future. We find that additional days above 80 °F cause a large decline in birth rates approximately 8 to 10 months later. The initial decline is followed by a partial rebound in births over the next few months implying that populations can mitigate the fertility cost of temperature shocks by shifting conception month. This dynamic adjustment helps explain the observed decline in birth rates during the spring and subsequent increase during the summer. The lack of a full rebound suggests that increased temperatures due to climate change may reduce population growth rates in the coming century. As an added cost, climate change will shift even more births to the summer months when third trimester exposure to dangerously high temperatures increases. Based on our analysis of historical changes in the temperature-fertility relationship, we conclude air conditioning could be used to substantially offset the fertility costs of climate change.

Maternal Bed Rest and Infant Health

Negative shocks to early child health influence both short- and long-run outcomes. Interventions prior to birth, rather than early in childhood, may reduce the probability or the severity of the shock and may be relatively cost effective. One such intervention, bed rest during pregnancy, is frequently prescribed to reduce the likelihood of preterm birth. Premature infants experience worse average initial infant health than full-term infants and these differences may persist into adulthood without mediation. Recent medical literature on the efficacy of bed rest is mixed, but tilts towards a negative or zero relationship between bed rest and infant health, suggesting that this intervention does not improve initial health status. This is not surprising given the difficulty of navigating a crucial threat to identification: conditions leading to bed rest recommendations are correlated with infant health. We investigate this question using Pregnancy Risk Assessment Monitoring System (PRAMS) data. Among women who experience a medical issue during pregnancy, we compare outcomes of infants born to mothers who are observationally similar yet differ in whether they are recommended bed rest. Using OLS and matching methods, we find a positive relationship between bed rest and the likelihood of low birth weight and prematurity (consistent with prior medical literature). Yet our results also show that bed rest decreases the incidence of very low birth weight (at least −15.4 percent), very premature outcomes (at least −7.7 percent), and a reduction for infant death. We provide additional evidence that suggests bed rest shifts initial health status upward. Our back-of-the-envelope calculations suggest that when accounting for cost savings over both the short and the long run, bed rest may be more cost-effective treatment than post-birth interventions.

Maybe Next Month? Temperature Shocks and Dynamic Adjustments in Birth Rates

We estimate the effects of temperature shocks on birth rates in the United States between 1931 and 2010. We find that days with a mean temperature above 80°F cause a large decline in birth rates 8 to 10 months later. Unlike prior studies, we demonstrate that the initial decline is followed by a partial rebound in births over the next few months, implying that populations mitigate some of the fertility cost by shifting conception month. This shift helps explain the observed peak in late-summer births in the United States. We also present new evidence that hot weather most likely harms fertility via reproductive health as opposed to sexual activity. Historical evidence suggests that air conditioning could be used to substantially offset the fertility costs of high temperatures.