The Indus Dictionary Project
This symbol is equivalent to the Chinese character nǚ 女. It is an ideograph for the adjective female or the noun woman.
Mohenjo-daro: Seal: M-840 a: Sayid Ghulam Mustafa Shah and Asko Parpola, 1991: Corpus of Indus Seals and Inscriptions: Volume 2: Page 75: Collections in Pakistan: Suomalainen Tiedeakatemia.
Mahadevan's sign number 1001 is the verb to deliver with the addtion of a horizontal line inside the body of the character. Females can, of course, deliver offspring from within their bodies. However, this explanation for the ideograph is only conjecture.
Indus Script Sign Number 1001: List of Sign Variants: Iravatham Mahadevan, 1977: The Indus Script: Texts, Concordance and Tables: The Director General Archaeological Survey of India.