"Constitutional" is simply a label. An important label to be sure, one that we should respect and one for which we should insist on high and rigorous standards. But it is not synonymous with consistent, just, fair, or rational.
However you want to describe it, you've taken the position that women have rights fundamentally that men do not have, simply because they are women. They have the women-only right to contraception at taxpayer expense; they have the women-only right to abort a man's child or to hold him financially accountable for that child, and either without his consent; and they have the women-only right to refuse military service in time of war.
You are free to call this "equality before the law", and in fact each of these things might be completely constitutional, but readers will draw their own conclusions on whether they are consistent, just, fair, or rational. And if women-only rights exist, then we are forced to consider that men-only, or whites-only, or straights-only, or Christians-only, rights might exist as well.
I haven’t taken any of those positions. You’re swinging at an empty straw man (perhaps because you have no actual argument to present).
Both the man and the woman have exactly the same rights and obligations with respect to the result of their intercourse: until the fetus is viable, each has the right to remove it from his or her own body - neither can be conscripted into becoming a walking incubator for the sake of a nonviable fetus. The fact that the fetus doesn’t implant in the man, and therefore that he cannot force the woman to abort the fetus if she does not want to does not make them unequal before the law because giving the man the power to force the woman to abort against her will would be to give him greater rights than she has. It is you who is arguing for inequality, not me.
Once the fetus is viable, neither can abort it, and therefore they are, still, on equal terms under the law.
Finally, once the child is born, they are both equally responsible for paying for it. Again, they are equal before the law. To give the man the right to not pay for his responsibilities would, again, be to give him more rights than the woman has. And so yet again, it is you who is arguing for inequality, not me.
The problem you have is the asymmetry of biology; but that was not created by law, and by itself does not give rise to inequality before the law. It is simply a fact.