This study aimed to assess whether LH surge characteristics influenced the likelihood of conceiving naturally.

This was a single-cycle, home-based, observational, case-controlled study. Volunteers collected daily urine samples for one menstrual cycle. LH was measured, and the basal levels, surge day, peak day, peak concentration, and magnitude of LH surges were examined.

The surge profile did not differ between cycles with early or late ovulation and was not affected by age or BMI. The mean LH surge day was day 16 for both groups. Mean LH surge and concentrations did not differ between groups. Sociodemographic characteristics were significant predictors of pregnancy, and sociodemographic variable-based models had the most significant predictive ability for conception, providing up to 65% predictive accuracy.

Sociodemographic variables can be used to predict the likelihood of a woman conceiving naturally. Provided an LH surge is present, its profile does not relate to the probability of spontaneous pregnancy. However, the conception rate was significantly lower in women with elevated or reduced basal levels of LH, suggesting that follicular maturation needs an optimal basal level of LH in natural conception cycles.