For the partner: the hours, the relationship, and the leave
Three findings that are measured, and one widely repeated claim that runs the other way.
The hours, from the federal time-use survey. Average hours per day spent caring for household children as a main activity:
| Youngest child | Fathers | Mothers | Gap |
|---|---|---|---|
| Under 6 | 1.66 | 2.53 | 0.87 h/day |
| 6 to 12 | 0.64 | 1.44 | 0.80 h/day |
On household activities across all adults, men average 1.58 hours a day and women 2.38. Two caveats make the real gap larger, not smaller: the household figures cover all adults rather than new parents, and the survey counts main activity only, which systematically misses the supervisory attention that falls disproportionately on mothers.
Those are absolute numbers from a federal survey. They need no interpretation and no argument.
The relationship. In 218 couples followed across eight years of marriage, parents showed a sudden deterioration in relationship quality after the birth, small to medium in size, which tended to persist. Mothers and fathers changed by similar amounts. What makes this study unusually credible is that it included couples who did not have children over the same period: they declined too, but gradually and without the cliff.
The study found the size of the drop varied between couples according to characteristics of the individual, the marriage and the pregnancy. It did not name them in a form this guide could verify, so no list is offered here.
Do not expect a programme to fix it. Across 142 randomized trials of parenting education for expectant and new parents, effects were described by the authors as small to very small, and the effect on couple adjustment was the second smallest of ten outcomes measured, at 0.13. Programmes may be worth doing for other reasons. Protecting the relationship is not a claim the evidence supports.
Fathers who took two weeks' leave: postpartum depression 4.5% against 5.7% in those who did not, odds ratio 0.74.
Mothers whose partner took leave: postpartum depression 16.1% against 15.3%, odds ratio 1.13, significantly higher.
The authors wrote:
offering 2-weeks' paternity leave might place mothers at a greater risk of post-partum depression, suggesting that optimal length and timing of the leave, among other factors, need further investigation.
The absolute difference in mothers is 0.8 percentage points, this is observational, and reverse causation is entirely plausible: a struggling mother may be exactly why a father takes his leave. But the standard claim should not be repeated as though this study did not exist.
A separate analysis of six US states with paid family leave found small benefits: breastfeeding duration 0.53 weeks longer and maternal depressive symptoms 0.93 percentage points lower, both with confidence intervals nearly touching zero. The authors also reported worsening of some birth outcomes, which they attributed to possible selection in utero, data limitations, or true negative effects. Note also that these are paid family leave policies, taken mostly by mothers. They are not a measurement of what partner leave does.
The United States is the only high-income country without a national paid family leave (PFL) policy.
A growing number of states have their own programmes, the number changes, and many of them include bonding leave a non-birthing partner can claim. A great many partners do not know that. It is worth checking what your state and your employer actually offer, rather than assuming.