Determination of gestational age from lunar age assessments in human fetal remains

Occasionally forensic fetal remains are submitted to the office of the medical examiner for age determination. A variety of literature and many techniques are available for this assessment depending upon the overall condition of the remains. If one uses traditional forensic anthropological sources, then age is calculated in lunar months; if one uses other sources--embryological, anthropological and sonographic--then age is reported as gestational weeks. For comparison between ages derived from these various studies, especially in cases involving age assessments of incomplete fetal remains that may be partially damaged by taphonomic factors, it is necessary to convert between lunar age and gestational age. The objective of this study is to present a conversion table for exact correspondence between lunar months and gestational weeks from the point of conception to term. This information is useful for developing a forensic profile at any gestational age as well as providing a means to assess the probability of viability at the time of death.