This is a slightly odd statement. I would agree with you regarding abortion rights falling under bodily autonomy but as the only people who can have abortions are women, it additionally makes it a sex based right.
It makes it the right to bodily autonomy. The first mention of Sex Based Rights I can find in Hansard is 2015 by Joanna Cherry. Prior to this the discourse has been focused on universal human rights, civil liberties and equalities for all marginalised groups. Women's rights are human rights: the recognition that women find it hard to access rights to healthcare, bodily autonomy because of systemic patriarchy.
Whereas voting really was a sex based right. You had to be a man in order to have the right to vote, and this changed when women campaigned during the First Wave Feminism. This led to the universal right of suffrage—voting for everyone over a certain age. Voting is not a 'sex based right'. It's a universal one.
Shifting the discourse on human rights to some watered down notion of 'sex based rights' does not fit with current jurisprudence or public international law, and legally speaking they don't exist. We have human rights, and civil and political rights, and the State has a responsibility to facilitate access to them for all marginalised groups. That's what 'women's rights' 'black rights' 'disability rights' or 'gay rights' means. It doesn't mean that people don't have rights on paper, it means they have trouble accessing them because of systemic inequalities.
The new term of 'sex based rights' was coined by GC Feminists who wanted to specifically exclude trans people from the women's movement, and turn what in the old days we'd just have called 'women's rights' to defining woman soley in terms of reproductive function.
Take your right to bodily autonomy, which includes the right to the correct reproductive healthcare for your body. This comes under Article 8 of the European Convention on Human Rights 1950, and Section 6 of the Human Rights Act 1998. Yes 'only someone with a womb can have an abortion' but that right of bodily autonomy IS universal. It covers men who need prostate cancer treatment, as well. A man's right to prostate cancer treatment isn't a separate 'sex based right'. It's just covered under the usual obligations of the State to provide appropriate care. The right to vote is no longer—thankfully—a 'sex based right'. It's a universal civil and political right. But back when 'votes for women' was the chief feminist ontological statement? Men genuinely thought that if women had rights of suffrage recognised they'd somehow LOSE their rights.
Be very ware of those who are telling you you will lose your rights if other people have theirs recognised or are allowed access to their rights. There's nearly always an agenda at work behind this. If you feel you're threatened, you can be convinced to get behind all sorts of abusive laws and behaviour.
Also, I am actually trained in human rights law and hold a masters in public international law. Prior to giving birth to DD, I worked for a major UK legal centre.